Private Delivery Services (PDSs)
You can use certain PDSs designated by the IRS to meet the “timely mailing as timely filing” rule for tax returns. Go to IRS.gov/PDS for the current list of PDSs.
The PDS can tell you how to get written proof of the mailing date.
For the IRS mailing address to use if you’re using a PDS, go to IRS.gov/PDSstreetAddresses . Select the mailing address listed on the webpage that is in the same state as the address to which you would mail returns filed without a payment, as shown in the instructions for your employment tax return.
PDSs can’t deliver items to P.O. boxes. You must use the U.S. Postal Service (USPS) to mail any item to an IRS P.O. box address.